It has long been recognized clinically that intracranial abnormalities and peptic ulcer disease coexist more frequently than would be expected by chance.1Experimentally it is possible to induce peptic ulcers by destruction or stimulation of a number of cerebral sites.2Because of its role as an integrative center for autonomic function, the hypothalamus has received considerable attention from investigators interested in the etiology of the neurogenic or stress ulcer. Gross localization of differing autonomic functions to certain areas within the hypothalamus has been frequently described in several animal species.3Our experiments have emphasized the importance of the frequency and pulse duration of the stimulating current in eliciting a sympathetic or parasympathetic response. We find that stimulation of the anteromedial region of the hypothalamus with low frequency, brief duration pulses produces primarily a parasympathetic response while stimulation of the posteromedial region of the hypothalamus with longer duration, higher